Triethylamine → [4-(4-Cyanophenyl)but-3-ynyl]carbamic acid tert-butyl ester

Participants

Reaction Steps

But-3-ynylcarbamic acid tert-butyl ester (3.66 g, 22 mmol) was added dropwise to an ice cooled, stirring, argon purged mixture of 4-iodobenzonitrile (4.5 g, 19.6 mmol), dichlorobis(triphenylphosphine)palladium(II) (0.69 g, 0.98 mmol), copper (I) iodide (0.19 g, 0.98 mmol), triethylamine (11 mL, 78.4 mmol), and THF (24 mL). After stirring for 10 min, the ice bath was removed, and the reaction was allowed to stir for an additional 2 h. The reaction mixture was passed through a pad of silica gel with methylene chloride/ethyl acetate (5:1) as eluant. After evaporating the solvent, the crude product was chromatographed with methylene chloride/ethyl acetate (20:1) as eluant. Evaporation of the solvent, followed by placement under vacuum for 1 h, afforded the pure product 56 (5.2 g, 99%) as an oil. 1H NMR (300 MHz, CDCl3) δ 1.46 (s, 9H), 2.64 (t, 2H), 3.37 (m, 2H), 4.85 (br s, 1H), 7.47 (d, 2H), 7.58 (d, 2H).

Provenance & Evidence